C_(60)/C_(70)及其衍生物(C_(60)Cl_n/C_(70)Cl_n)在丁二烯阴离子聚合中的偶联作用

COUPLING EFFECT OF C_(60)/C_(70) AND ITS DERIVATIVE (C_(60)Cl_n/C_(70)Cl_n) IN ANIONIC POLYMERIZATION OF BUTADIENE

The fullerenes chloride,C 60 Cl n /C 70 Cl n, was used as a novel coupling agent in n BuLi initiated anionic polymerization of butadiene(Bd).Its coupling behavior was investigated by comparing with the commonly used coupling agent SiCl 4.The broader polydispersity of the coupling products and a new peak in GPC chromatograms demonstrated that coupling reactions happened and polybutadiene chains were covalently bonded to the molecule of C 60 Cl n /C 70 Cl n .But the coupling efficiency needs to be improved.The intrinsic viscosity of the coupling products([ η ]) was also measured.Double peaks in the coupling agent curves appeared when C 60 Cl n /C 70 Cl n was used,while a single peak in the coupling agent curves occurred when SiCl 4 was used.The results above showed that C 60 Cl n /C 70 Cl n had the specific coupling mechanisms which were different from SiCl 4.Two coupling mechanisms of C 60 Cl n /C 70 Cl n including addition and substitution were deduced.The experiment also revealed that in the anionic polymerization of Bd,the molecule C 60 could influence the polymerization.A new living center formed in the reaction system by n BuLi and C 60 might be able to initiate the polymerization of Bd,which increased the products’ molar mass and broadened polydispersity.The structure of the star shaped products with polybutadiene as arms and C 60 Cl n /C 70 Cl n as core should be studied further.

The fullerenes chloride,C-60 Cl-n/C-70 Cl-n, was used as a novel coupling agent in n-BuLi initiated anionic polymerization of butadiene (Bd). Its coupling behavior was investigated by comparing with the commonly used coupling agent SiCl4. The broader polydispersity of the coupling products a new peak in GPC chromatograms demonstrated that coupling reactions happened and polybutadiene chains were covalently bonded to the molecule of C60Cln/C70Cln. But the coupling efficiency needs to be improved. The intrinsic viscosity of the coupling products ([eta]) was also measured. Double peaks in the coupling agent curves appeared when C60Cln/C70Ca was used,while a single peak in the coupling agent curves occurred when SiCl4 was used. The results above showed that C60Cln/C-70 Cl-n had the specific coupling mechanisms which were different from SiCl4. Two coupling mechanisms of C60Cla/C-70 Cl-n including addition and substitution were deduced. The experiment also revealed that in the anionic polymerization' of Bd, the molecule C-60 could influence the polymerization. A new living center formed in the reaction system by n-BuLi and C-60 might be able to initiate the polymerization of Bd, which increased the products' molar mass and. broadened polydispersity. The structure of the star-shaped products with polybutadiene as arms and C60Cln/C70Cln as core should be,studied further.